Theme Editor: added "Pick Color from Screen" action to "Edit" menu that allows picking a color from anywhere on screen and insert/change it at caret position

flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatColorPipette.java

@@ -0,0 +1,278 @@
+/*
+ * Copyright 2021 FormDev Software GmbH
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.formdev.flatlaf.themeeditor;
+
+import java.awt.AWTException;
+import java.awt.BasicStroke;
+import java.awt.BorderLayout;
+import java.awt.Color;
+import java.awt.Component;
+import java.awt.Graphics;
+import java.awt.Graphics2D;
+import java.awt.Insets;
+import java.awt.Rectangle;
+import java.awt.Robot;
+import java.awt.Window;
+import java.awt.Dimension;
+import java.awt.EventQueue;
+import java.awt.event.KeyAdapter;
+import java.awt.event.KeyEvent;
+import java.awt.event.MouseAdapter;
+import java.awt.event.MouseEvent;
+import java.awt.image.BufferedImage;
+import java.util.function.Consumer;
+import javax.swing.JComponent;
+import javax.swing.JDialog;
+import javax.swing.JLabel;
+import javax.swing.JWindow;
+import javax.swing.SwingUtilities;
+import com.formdev.flatlaf.icons.FlatAbstractIcon;
+import com.formdev.flatlaf.ui.FlatEmptyBorder;
+import com.formdev.flatlaf.ui.FlatLineBorder;
+import com.formdev.flatlaf.util.HSLColor;
+import com.formdev.flatlaf.util.UIScale;
+
+/**
+ * @author Karl Tauber
+ */
+class FlatColorPipette
+{
+	/**
+	 *
+	 *
+	 * @throws AWTException if platform does not allow using robot (e.g. if headless)
+	 * @throws UnsupportedOperationException if platform does not support translucent window
+	 */
+	static void pick( Window owner, boolean modal,
+			Consumer<Color> hoverCallback, Consumer<Color> pickCallback )
+		throws AWTException, UnsupportedOperationException
+	{
+		InvisiblePickWindow pickWindow = new InvisiblePickWindow( owner, modal, hoverCallback, pickCallback );
+		pickWindow.setVisible( true );
+	}
+
+	//---- class InvisiblePickWindow ------------------------------------------
+
+	/**
+	 * An invisible window used to receive mouse and keyboard events for the whole screen.
+	 */
+	private static class InvisiblePickWindow
+		extends JDialog
+	{
+		private final Consumer<Color> hoverCallback;
+		private final Consumer<Color> pickCallback;
+
+		private final Robot robot;
+		private final Magnifier magnifier;
+
+		private int lastX;
+		private int lastY;
+		private Color lastHoverColor;
+
+		InvisiblePickWindow( Window owner, boolean modal,
+				Consumer<Color> hoverCallback, Consumer<Color> pickCallback )
+			throws AWTException, UnsupportedOperationException
+		{
+			super( owner, modal ? ModalityType.APPLICATION_MODAL : ModalityType.MODELESS );
+			this.hoverCallback = hoverCallback;
+			this.pickCallback = pickCallback;
+
+			setAlwaysOnTop( true );
+			setUndecorated( true );
+			setOpacity( 0.005f );
+			setBounds( owner.getGraphicsConfiguration().getBounds() );
+
+			robot = new Robot( owner.getGraphicsConfiguration().getDevice() );
+			magnifier = new Magnifier( this, robot );
+
+			MouseAdapter mouseListener = new MouseAdapter() {
+				@Override
+				public void mouseMoved( MouseEvent e ) {
+					lastX = e.getX();
+					lastY = e.getY();
+
+					// get color at mouse location
+					// (temporary change opacity to zero to get correct color from robot)
+					float oldOpacity = getOpacity();
+					setOpacity( 0 );
+					Color color = robot.getPixelColor( lastX, lastY );
+					setOpacity( oldOpacity );
+
+					hover( color );
+					magnifier.update( lastX, lastY, color );
+				}
+
+				@Override
+				public void mouseClicked( MouseEvent e ) {
+					dispose();
+
+					if( SwingUtilities.isLeftMouseButton( e ) )
+						pick( robot.getPixelColor( e.getX(), e.getY() ) );
+					else
+						pick( null );
+				}
+			};
+
+			KeyAdapter keyListener = new KeyAdapter() {
+				@Override
+				public void keyPressed( KeyEvent e ) {
+					switch( e.getKeyCode() ) {
+						case KeyEvent.VK_ESCAPE: dispose(); pick( null ); break;
+
+						// move mouse one pixel using arrow keys
+						case KeyEvent.VK_LEFT:  robot.mouseMove( lastX - 1, lastY ); break;
+						case KeyEvent.VK_RIGHT: robot.mouseMove( lastX + 1, lastY ); break;
+						case KeyEvent.VK_UP:    robot.mouseMove( lastX, lastY - 1 ); break;
+						case KeyEvent.VK_DOWN:  robot.mouseMove( lastX, lastY + 1 ); break;
+					}
+				}
+			};
+
+			addMouseListener( mouseListener );
+			addMouseMotionListener( mouseListener );
+			addKeyListener( keyListener );
+
+			magnifier.addMouseListener( mouseListener );
+			magnifier.addMouseMotionListener( mouseListener );
+			magnifier.addKeyListener( keyListener );
+
+			magnifier.pack();
+		}
+
+		private void hover( Color color ) {
+			if( hoverCallback == null || color == null || color.equals( lastHoverColor ) )
+				return;
+
+			lastHoverColor = color;
+
+			EventQueue.invokeLater( () -> {
+				hoverCallback.accept( color );
+			} );
+		}
+
+		private void pick( Color color ) {
+			EventQueue.invokeLater( () -> {
+				pickCallback.accept( color );
+			} );
+		}
+	}
+
+	//---- class Magnifier ----------------------------------------------------
+
+	private static class Magnifier
+		extends JWindow
+	{
+		private final Window owner;
+		private final Robot robot;
+
+		private final MagnifierView view;
+		private final JLabel infoLabel;
+
+		private final int zoom;
+		private final int pixels = 16;
+		private Color colorAtMouse;
+		private BufferedImage image;
+
+		public Magnifier( Window owner, Robot robot ) {
+			super( owner );
+			this.owner = owner;
+			this.robot = robot;
+
+			zoom = UIScale.scale( 16 );
+
+			getRootPane().setBorder( new FlatLineBorder( new Insets( 2, 2, 2, 2 ), Color.red, 2 ) );
+
+			view = new MagnifierView();
+			view.setPreferredSize( new Dimension( pixels * zoom, pixels * zoom ) );
+
+			infoLabel = new JLabel( "#" );
+			infoLabel.setIcon(  new ColorIcon() );
+			infoLabel.setBorder( new FlatEmptyBorder( 4, 4, 4, 4 ) );
+
+			add( view, BorderLayout.CENTER );
+			add( infoLabel, BorderLayout.SOUTH );
+		}
+
+		void update( int x, int y, Color colorAtXY ) {
+			colorAtMouse = colorAtXY;
+
+			// capture screen at mouse location
+			image = robot.createScreenCapture( new Rectangle( x - (pixels / 2), y - (pixels / 2), pixels, pixels ) );
+
+			// update color in info label
+			HSLColor hslColor = new HSLColor( colorAtMouse );
+			int hue = Math.round( hslColor.getHue() );
+			int saturation = Math.round( hslColor.getSaturation() );
+			int luminance = Math.round( hslColor.getLuminance() );
+			infoLabel.setText( String.format( "#%06x   HSL %d %d %d",
+				colorAtMouse.getRGB() & 0xffffff, hue, saturation, luminance ) );
+
+			// place bottom-right to mouse location
+			int mx = x + UIScale.scale( 32 );
+			int my = y + UIScale.scale( 32 );
+
+			// make sure that it is within screen
+			if( mx + getWidth() > owner.getX() + owner.getWidth() )
+				mx = x - getWidth() - UIScale.scale( 32 );
+			if( my + getHeight() > owner.getY() + owner.getHeight() )
+				my = y - getHeight() - UIScale.scale( 32 );
+
+			setLocation( mx, my );
+			setVisible( true );
+			repaint();
+		}
+
+		//---- class MagnifierView ----
+
+		private class MagnifierView
+			extends JComponent
+		{
+			@Override
+			public void paint( Graphics g ) {
+				int width = getWidth();
+				int height = getHeight();
+
+				if( image != null )
+					g.drawImage( image, 0, 0, width, height, null );
+
+				int xy = (pixels / 2) * zoom;
+				g.setColor( Color.red );
+				((Graphics2D)g).setStroke( new BasicStroke( 2 ) );
+				g.drawRect( xy - 1, xy - 1, zoom + 2, zoom + 2 );
+			}
+		}
+
+		//---- class ColorIcon ----
+
+		private class ColorIcon
+			extends FlatAbstractIcon
+		{
+			private static final int WIDTH = 64;
+			private static final int HEIGHT = 16;
+
+			public ColorIcon() {
+				super( WIDTH, HEIGHT, null );
+			}
+
+			@Override
+			protected void paintIcon( Component c, Graphics2D g ) {
+				g.setColor( colorAtMouse );
+				g.fillRect( 0, 0, WIDTH, HEIGHT );
+			}
+		}
+	}
+}

flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatSyntaxTextArea.java

@@ -36,6 +36,7 @@ import org.fife.ui.rtextarea.RTextAreaUI;
 import org.fife.ui.rtextarea.RUndoManager;
 import com.formdev.flatlaf.UIDefaultsLoaderAccessor;
 import com.formdev.flatlaf.themeeditor.FlatSyntaxTextAreaActions.InsertColorAction;
+import com.formdev.flatlaf.themeeditor.FlatSyntaxTextAreaActions.PickColorAction;
 import com.formdev.flatlaf.themeeditor.FlatSyntaxTextAreaActions.DuplicateLinesAction;
 import com.formdev.flatlaf.themeeditor.FlatSyntaxTextAreaActions.IncrementNumberAction;
 
@@ -68,6 +69,7 @@ class FlatSyntaxTextArea
 		actionMap.put( FlatSyntaxTextAreaActions.incrementNumberAction, new IncrementNumberAction( FlatSyntaxTextAreaActions.incrementNumberAction, true ) );
 		actionMap.put( FlatSyntaxTextAreaActions.decrementNumberAction, new IncrementNumberAction( FlatSyntaxTextAreaActions.decrementNumberAction, false ) );
 		actionMap.put( FlatSyntaxTextAreaActions.insertColorAction, new InsertColorAction( FlatSyntaxTextAreaActions.insertColorAction ) );
+		actionMap.put( FlatSyntaxTextAreaActions.pickColorAction, new PickColorAction( FlatSyntaxTextAreaActions.pickColorAction ) );
 
 		// add editor key strokes
 		InputMap inputMap = getInputMap();

flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatSyntaxTextAreaActions.java

@@ -16,6 +16,7 @@
 
 package com.formdev.flatlaf.themeeditor;
 
+import java.awt.AWTException;
 import java.awt.Color;
 import java.awt.Component;
 import java.awt.Point;
@@ -43,6 +44,7 @@ class FlatSyntaxTextAreaActions
 	static final String incrementNumberAction = "FlatLaf.IncrementNumberAction";
 	static final String decrementNumberAction = "FlatLaf.DecrementNumberAction";
 	static final String insertColorAction = "FlatLaf.InsertColorAction";
+	static final String pickColorAction = "FlatLaf.PickColorAction";
 
 	static int[] findColorAt( RTextArea textArea, int position ) {
 		try {
@@ -384,4 +386,76 @@ class FlatSyntaxTextAreaActions
 			return getName();
 		}
 	}
+
+	//---- class PickColorAction ----------------------------------------------
+
+	static class PickColorAction
+		extends RecordableTextAction
+	{
+		PickColorAction( String name ) {
+			super( name );
+		}
+
+		@Override
+		public void actionPerformedImpl( ActionEvent e, RTextArea textArea ) {
+			try {
+				// find current color at caret
+				int caretPosition = textArea.getCaretPosition();
+				int start;
+				int len = 0;
+				String oldStr;
+				int[] result = findColorAt( textArea, caretPosition );
+				if( result != null ) {
+					start = result[0];
+					len = result[1];
+
+					oldStr = textArea.getText( start, len );
+				} else {
+					start = caretPosition;
+					oldStr = "";
+				}
+
+				AtomicInteger length = new AtomicInteger( len );
+				AtomicBoolean changed = new AtomicBoolean();
+
+				// show pipette color picker
+				Window window = SwingUtilities.windowForComponent( textArea );
+				FlatColorPipette.pick( window, true,
+					color -> {
+						// update editor immediately for live preview
+						String str = colorToString( color );
+						((FlatSyntaxTextArea)textArea).runWithoutUndo( () -> {
+							textArea.replaceRange( str, start, start + length.get() );
+						} );
+						length.set( str.length() );
+						changed.set( true );
+					},
+					color -> {
+						// restore original string
+						((FlatSyntaxTextArea)textArea).runWithoutUndo( () -> {
+							textArea.replaceRange( oldStr, start, start + length.get() );
+						} );
+						length.set( oldStr.length() );
+
+						// update editor
+						if( color != null ) {
+							String newStr = colorToString( color );
+							try {
+								if( !newStr.equals( textArea.getText( start, length.get() ) ) )
+									textArea.replaceRange( newStr, start, start + length.get() );
+							} catch( BadLocationException ex ) {
+								ex.printStackTrace();
+							}
+						}
+					} );
+			} catch( BadLocationException | IndexOutOfBoundsException | NumberFormatException | UnsupportedOperationException | AWTException ex ) {
+				ex.printStackTrace();
+			}
+		}
+
+		@Override
+		public String getMacroID() {
+			return getName();
+		}
+	}
 }

flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatThemeFileEditor.java

@@ -657,6 +657,12 @@ class FlatThemeFileEditor
 			themeEditorPane.notifyTextAreaAction( FlatSyntaxTextAreaActions.insertColorAction );
 	}
 
+	private void pickColor() {
+		FlatThemeEditorPane themeEditorPane = (FlatThemeEditorPane) tabbedPane.getSelectedComponent();
+		if( themeEditorPane != null )
+			themeEditorPane.notifyTextAreaAction( FlatSyntaxTextAreaActions.pickColorAction );
+	}
+
 	private void showHidePreview() {
 		boolean show = previewMenuItem.isSelected();
 		for( FlatThemeEditorPane themeEditorPane : getThemeEditorPanes() )
@@ -888,6 +894,7 @@ class FlatThemeFileEditor
 		editMenu = new JMenu();
 		findMenuItem = new JMenuItem();
 		insertColorMenuItem = new JMenuItem();
+		pickColorMenuItem = new JMenuItem();
 		viewMenu = new JMenu();
 		previewMenuItem = new JCheckBoxMenuItem();
 		lightLafMenuItem = new JRadioButtonMenuItem();
@@ -986,6 +993,12 @@ class FlatThemeFileEditor
 				insertColorMenuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_G, KeyEvent.CTRL_DOWN_MASK));
 				insertColorMenuItem.addActionListener(e -> insertColor());
 				editMenu.add(insertColorMenuItem);
+
+				//---- pickColorMenuItem ----
+				pickColorMenuItem.setText("Pick Color from Screen");
+				pickColorMenuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_G, KeyEvent.CTRL_DOWN_MASK|KeyEvent.SHIFT_DOWN_MASK));
+				pickColorMenuItem.addActionListener(e -> pickColor());
+				editMenu.add(pickColorMenuItem);
 			}
 			menuBar.add(editMenu);
 
@@ -1150,6 +1163,7 @@ class FlatThemeFileEditor
 	private JMenu editMenu;
 	private JMenuItem findMenuItem;
 	private JMenuItem insertColorMenuItem;
+	private JMenuItem pickColorMenuItem;
 	private JMenu viewMenu;
 	private JCheckBoxMenuItem previewMenuItem;
 	private JRadioButtonMenuItem lightLafMenuItem;

flatlaf-theme-editor/src/main/java/com/formdev/flatlaf/themeeditor/FlatThemeFileEditor.jfd

@@ -1,4 +1,4 @@
-JFDML JFormDesigner: "7.0.4.0.360" Java: "16" encoding: "UTF-8"
+JFDML JFormDesigner: "7.0.5.0.382" Java: "16" encoding: "UTF-8"
 
 new FormModel {
 	contentType: "form/swing"
@@ -112,6 +112,12 @@ new FormModel {
 						"accelerator": static javax.swing.KeyStroke getKeyStroke( 71, 130, false )
 						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "insertColor", false ) )
 					} )
+					add( new FormComponent( "javax.swing.JMenuItem" ) {
+						name: "pickColorMenuItem"
+						"text": "Pick Color from Screen"
+						"accelerator": &KeyStroke0 static javax.swing.KeyStroke getKeyStroke( 71, 195, false )
+						addEvent( new FormEvent( "java.awt.event.ActionListener", "actionPerformed", "pickColor", false ) )
+					} )
 				} )
 				add( new FormContainer( "javax.swing.JMenu", new FormLayoutManager( class javax.swing.JMenu ) ) {
 					name: "viewMenu"